If a patient has dentine hypersensitivity, can thermal stimuli damage the dentine?

Question

As defined by this paper:

Dentine hypersensitivity is characterized by short, sharp pain arising from exposed dentine in response to stimuli, typically thermal, evaporative, tactile, osmotic or chemical and which cannot be ascribed to any other dental defect or pathology.

In a typical case of dentine hypersensitivity, does thermal stimuli:

• Trigger a sharp sensation of pain without actually damaging the dentine
• Trigger a sharp sensation pain caused by physical damage to the dentine

Consider the case where a patient suffering from dentine hypersensitivity is taking painkillers, rendering them unable to feel pain from thermal stimuli.

Is there any reason this patient should avoid thermal stimuli, such as an ice-cold beverage?

I am not asking if it is advisable to take painkillers for dentine hypersensitivity. A patient could be taking painkillers for any number of non-dentine hypersensitivity reasons, such as back pain.

Answer 1

No, the hot or cold stimuli do not cause damage to the dentine, unless the cold or the heat is truly extream and prolonged.

To understand what is going on, one has to know that dentine is a highly organised structure composed of thousands of tubules (microscopic channels). These spaces are occupied by air, fluid or the extremities of odontoblasts, cells that produced the dentin, which are at the periphery of the pulp chamber, the center of the tooth. The nerves in the middle of the tooth are only capable of transmitting information about pain and are unable to discriminate between the various causes.

One of the most accepted theories to explain dentine sensitivity was the hydromechanical theory by Dr. Martin Brännström. The pain is caused by the movement of fluid in the tubules due to changes in temperature and pressure. Pressure on the tooth or a hot stimulus cause the fluid to expand inwards and compress the odontoblasts and nerves in the middle of the tooth. Prolonged drying or a cold stimulus causes the water in the tubules to contract outwards (toward the stimulus), which causes a suction of the odontoblasts into the tubules which in turn pull on the nerves in the middle of the tooth, again causing discomfort or pain.

Lastly, over-the-counter analgesics (painkillers) will not be very effective at preventing the pain, and more powerful ones will only mask the pain temporarily. Use of special toothpaste to block the tubules and desensitise the nerves can work, but an examination by an oral health professional will make sure that there is truly no other factors at play.

My sources, other than professional training:

Brannstrom, M. (1963). "Dentin sensitivity and aspiration of odontoblasts." Journal of the American Dental Association 66: 366-370.